Severely threatening events and marked life difficulties preceding onset or exacerbation of multiple sclerosis.

<b>Introduction:</b> Obstructive sleep apnoea (OSA) is a sleep disorder that remains under-diagnosed. Improved detection depends on increased public awareness. <b>Aims:</b> To assess awareness and knowledge of OSA in the population of a multiethnic Asian nation. <b>Methods:</b> The Singapore Health Study 2012 was a cross-sectional population-based study. A sample of 256 subjects completed the STOP-Bang questionnaire and a home-based sleep study. Moderate-to-severe OSA was defined as an apnoea-hypopnoea index (AHI) ≥15. Participants were then contacted by phone to complete a questionnaire assessing awareness and knowledge of OSA. <b>Results:</b> There were 217 completed surveys (response rate 84.8%) with 131 male participants (51.2%). Only 78 (35.9%) could correctly define OSA. A total of 48 (22.1%) and 80 (36.9%) respondents correctly listed ≥1 risk factor or symptom for OSA, respectively. Among 84 respondents with a STOP-Bang score ≥ 3, 24 (28.6%) correctly defined OSA, 16 (19.0%) correctly listed ≥1 risk factors and 29 (34.5%) correctly listed ≥1 symptoms. Among 61 respondents who had AHI ≥15, 11 (18.0%) correctly defined OSA, 6 (9.8%) correctly listed ≥1 risk factors and 11 (18.0%) correctly listed ≥1 symptoms. Significant predictors for incorrectly defining OSA included a low education (odds ratio (OR) 0.04, 95% confidence interval (CI) 0.007-0.18), ethnicity (Chinese baseline; Malay OR 0.44, 95% CI 0.20-0.93; Indian OR 0.31, 95% CI 0.14-0.73) and a diagnosis of moderate-to-severe OSA on the home-based sleep study (OR 0.28, 95% CI 0.12-0.62). <b>Conclusion:</b> Public awareness and knowledge of OSA is poor. Respondents with moderate-to-severe OSA had the least knowledge. Considerable educational effort is needed to increase awareness.